This invention relates generally to process systems, and more specifically to methods and systems for improving operation of pressure vessels used in gasification systems.
At least some known vessels include an annular space located near a vertically upper hemispherical head or dome of the vessel. The annular space may be used to consolidate piping ends into headers that channel the flow of fluid in the pipes to and from external to the vessel. Such piping may result in complex pipe routing that reduces a capability to effectively maintain the vessel. Specifically, a refractory lined throat that carries hot fluid into the vessel from, for example, a gasifier may be difficult to maintain because of the piping located in the head. The hot fluid may leak into the annular space from inside the throat. The leaking fluid may include corrosive gases that over time may shorten the life of components in the upper hemispherical head. Moreover, the refractory lined throat that carries hot fluid from the gasifier into the vessel tends to overheat.
Furthermore, various materials and various thicknesses of the materials may be used in the fabrication of the vessel, head, and/or components within the vessel and head. Because such materials and various thicknesses of materials may expand and contract at different rates when exposed to changing temperatures within the vessel. Thermal stresses may be generated that exceed the strength and/or the cycle fatigue rating of the vessel, head, and/or components.